Selecting molecules with a larger molecular weight, such as PVPK90, to treat the pigments, the treated pigments have the following advantages
a) Since the coating is insoluble in organic media, there will be no pigment diffusion when it is used.
b) After a layer of high-molecular polymer is coated on the surface of the pigment, the contact between the azo group of the organic pigment and the external medium is blocked, thus preventing the photochemical reduction reaction between the azo group and the external medium triggered by ultraviolet light, which greatly improves the light fastness.
c) Increase the gloss of the paint film and avoid rough cracks.
d) Easy to crush, enhancing coloring ability
